package com.tjetc._2string;

public class _6StringBuilder {
    public static void main(String[] args) {
        /*
            StringBuilder:
            1.底层也是维护了一个byte[] value
            2.线程不安全的
            3.效率最快
         */
        // 底层调用了StringBuilder
        String a = "a";
        a += "b";
    }
}
